You say he's active. How about Go Karting? This was a favourite with my son for birthdays around that age.
Then we would feed them pizzas at home afterwards, always a winner.
Cinema is good, but depending on how grownup they think they are, maybe a pizza in somewhere like pizza express afterwards?

Rib ride on the Thames from by the London Eye? Walking over the top of the O2? My 12 year old has done both of these for parties - great fun. Paintball is also good fun for active kids, but you normally need to drive out of town for it.